KVM: arm/arm64: Register iodevs when setting redist base and creating VCPUs

Instead of waiting with registering KVM iodevs until the first VCPU is
run, we can actually create the iodevs when the redist base address is
set.  The only downside is that we must now also check if we need to do
this for VCPUs which are created after creating the VGIC, because there
is no enforced ordering between creating the VGIC (and setting its base
addresses) and creating the VCPUs.

Signed-off-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index 0ea64a1beff9..962bb577a1a0 100644
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -226,6 +226,27 @@ static int kvm_vgic_dist_init(struct kvm *kvm, unsigned int nr_spis)
 	return 0;
 }
 
+/**
+ * kvm_vgic_vcpu_init() - Register VCPU-specific KVM iodevs
+ * @vcpu: pointer to the VCPU being created and initialized
+ */
+int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
+{
+	int ret = 0;
+	struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+	if (!irqchip_in_kernel(vcpu->kvm))
+		return 0;
+
+	/*
+	 * If we are creating a VCPU with a GICv3 we must also register the
+	 * KVM io device for the redistributor that belongs to this VCPU.
+	 */
+	if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
+		ret = vgic_register_redist_iodev(vcpu);
+	return ret;
+}
+
 static void kvm_vgic_vcpu_enable(struct kvm_vcpu *vcpu)
 {
 	if (kvm_vgic_global_state.type == VGIC_V2)